The invention relates to a method and apparatus for establishing parallel data network and telephone network communications to facilitate a collaboration combining the data transfer and document sharing strengths of a data network with the superior audio communication of a telephone network.
Communication over distances is important for the organization and completion of work in modem life. Examples of well-established forms of communication include telephone communication; and video communication through the use of existing teleconferencing facilities. The introduction of computers has given rise to a number of newer communication applications. These include voice over the Internet and video over the Internet. They also include applications that share data, including wordprocessing documents (and any graphical images incorporated therein) and presentation documents. In particular, some applications allow multiple users to simultaneously share and alter a common document. Known communication systems also include file sharing (often through an ftp protocol), xe2x80x9cchatxe2x80x9d lines and whiteboards.
It is known to collect data and voice communications into a combined application on a data network so these forms of communication can be used simultaneously for collaboration. An example of such an application is Microsoft(trademark) NetMeeting(trademark), which combines capability for video and audio communication, application sharing, file transfer, whiteboard, and chat.
The performance of such collaboration products is constrained by the available bandwidth: the rate at which information can be transmitted between computers. Typically, such constraints are reflected in poor audio and poor video performance. For example, the book xe2x80x9cOfficial Microsoft NetMeeting Bookxe2x80x9d (Bob Summers, Microsoft Press, 1998) lists the following commonly encountered problems at p. 10:
there is a delay in your voice;
the audio is not full-duplex, which means only one person can speak at one time;
the audio often crackles, or pauses, and an occasional word or two disappears;
the video is small, fuzzy, and movement is jerky.
In addition, deterioration in performance, most often manifested in poor audio performance, is increased as the amount of information passing simultaneously between users increases.
These issues are complicated when the communication and sharing does not take place inside a Local Area Network (or LAN, a data network typically used within a single organization) but instead travels over the Internet. Data over the Internet and on many LANs, including those connected to the Internet, accords to the Internet Protocol (IP). There are several levels in the IP. Prudent information technology management practice includes placing a xe2x80x9cfirewallxe2x80x9d between the Internet and a LAN, which functions by examining incoming data from the Internet and blocking signals that are not formatted in certain (usually high-level) IPs. Firewalls are also used on LANs to mask the IP addresses of computers behind the firewall. This ensures that data must first be sent through the firewall to a web server associated with the firewall before being passed on to the destination computer. (Such data must typically contain some identifier of the destination computer which is recognizable by the web server. The web server will match the identifier against a list of IP addresses to determine the IP address of the destination computer. The web server will then transmit the data to the destination computer across the LAN.)
Most of the data passed between users in a collaboration can be passed using the highlevel Transfer Control Protocol (TCP) which is not blocked in a typical firewall configuration. The International Telecommunications Union (ITU) standard for data sharing in collaboration applications, T.120, is a TCP format. Although the ITU standard for video and audio call setup and control, H.323, is also a TCP format, the actual transfer of audio and video information occurs using the lower-level User Diagram Protocol (UDP), which is often blocked by intervening firewalls. Furthermore, audio and video transmissions often use secondary connections (additional communication connections made simultaneously after a first connection) which are also often disallowed by firewalls. As a result, video and audio communication can be severely restricted or even blocked if it must pass through a firewall. Although firewalls can be configured specifically to allow video and audio communication activities, this involves configuring the system to allow uncontrolled inquiries, which significantly compromises system security and may be an unacceptable risk to many system administrators.
The present invention provides a method to set up parallel data (e.g. Internet) and telephone connections for non-voice collaboration communications and voice communications, respectively. This allows the combination of the general collaboration information sharing, such as whiteboarding and shared wordprocessing documents, with the superior voice performance of telephone connections. It will also allow greater use of collaboration over the Internet between LANs, as the voice communications which cause the greatest difficulty with firewalls are removed from the Internet to the telephone network.
In accordance with the present invention, there is provided a method for establishing a collaborative session between a calling station and a called station, comprising: receiving an identifier of a first station and a second station, each of said first station and second station comprising a telephone connected to a switched telephone network and a computer connected to a data network; causing establishment of a telephone connection between said telephone of said first station and said telephone of said second station over said switched telephone network where such a connection does not already exist; commanding said computer of said first station to launch a collaborative session with said computer of said second station over said data network with audio disabled.
The invention also contemplates a computer readable medium, computer data signal, and apparatus for carrying out this method.